Hobbing machine



. E.y STAPLES 2,127,273

HOBBING MACHINE Filed Feb.- e, 1937 k l /0 L 7l Z9 C' Qn- /Z [rll E t- M5/w 2f Hf 1%- "EH u f/f@ i im V D, n 1| I "z/ I 30 z/ Il I 'illu X13 z f h, I /5 f7 y- 1- i811 Il a /5 M j. 2z Y x /7 i 'nl' zo r I /J' f I W l 'f (f I J I /z l E f ,l

||x\ I y TT.) u I r T 1 H l L l I f l 'INVENTORA 077s E .STQPAES ATTORNEYS Patented Aug. 16, 1938 lUlsu'rlzo STATES HOBBING MACHINE Otis E. Staples, Cleve-land,l Ohio, assignor to The Cleveland Hobbing Machine Company, Cleveland, Ohio, a. corporation of Ohio Application February 6, 193:7, sefiaiNa 124,440

2 Claims.

Thepresent invention relates to metal working machines and more particularly to a mechanical chuckl especially adapted for use with hobbing machines of the multiple unit rotary turret type such as shown and described in U. S. patent to Frank I-l.V Adams et al., No. 2,048,173.

Prior to the present invention considerable difculty has been'encountered in holding certain pieces of work, especially those which must be held and driven solely from the inside thereof, in machines of the type referred to. The prior art devices available for this purpose either do not exert sufiicient force to satisfactorily hold the work blankY against slipping during the cut- 15,' ting operation or are too cumbersome or too difcult to operate in the space and time determined by satisfactory present day mass production requirements.` Fluid pressure, such as air, operated chucks which have the necessary re- 219 quirements of being capable of exerting immense force and'at thesame time being relatively operated to engage and disengage the work, do not operate satisfactorily on the aforesaid machines because of the difficulty of obtaining an unfaltergg ing supply of air at the chucks due to the rotation of the turret. Electrically operated chucks are subject to similar objections.

With the foregoing in mind an object of the present invention is the provision of a novel and 30 improved mechanical chuck as distinguished from a fluid pressure or electrically actuated one, which will securely hold a work blank, and which can be readily and easily actuated to engage or release the work as required.

Another object of the present invention is the provision of a novel and improved mechanical chuck comprising a heavy spring for causing the chuck to engage a work piece and a readily accessible and easily actuated cam for releasing the work against the action of the spring.

The present invention resides in certain novel details of construction, combinations and arrangements of parts, and further objects and advantages thereof will be apparent from the following description of the preferred embodiment thereof, described with reference to the accompanying drawing forming a part of this specication, in which similar reference characters designate corresponding parts, and in which:

Fig. 1 is a section through a work spindle of one of the hobbing units of a multiple unit hobbing machine similar to that shown in the aforesaid patent but provided with chucks embodying the present invention.

55 Fig. 2 is a section on the line 2-2 of Fig. 1.

:Fig 3 is a side View of the chuck shown in Fig. l with a part of the bearing shield broken away to show the rollers and cam inside thereof.

As previously'stated the present invention is especially applicable to multiple unit rotary hob- 5 bing machines and is herein shown andfdescribed as applied to such a machine. The machine per se forms no part of the present invention and is not entirely shown in the drawing or herein described in detail.

yFor the purpose of the present invention it is sufficient to say that the machine is fullyillustrated and described in the aforesaid patent to Frank H..Adams et al. to which reference is made for a complete description of the machine. 15 In the present drawing the turret is designated generallyby the reference character A, the work headby the reference character B, thel tail stop by the reference character C, the work spindle by the reference character D, and the driving 20 mechanism for the work spindle andthe feed movement of the work head by the reference character E.

The chuck shown comprises a body member or work arbor I0 fixed to the upper end of the work '25 spindle in any suitable manner as by the bolts II, and a centering member or plug I2, the lower tapered end of which projects into the work spindle while the head thereof extends above the spindle and fits into a counterbore in the lower 30 end of the work arbor. The plug I2 is used primarily to center the chuck with respect to the axis of rotation of the spindle D. The upper reduced end I3 of the work arbor Il) is provided with a plurality of radial slots I4 in which workengaging jaws I5 are slidably supported for movement radially of the axis of the longitudinal work arbor and the axis of rotation of the spindle. The work-engaging jaws I5 are adapted to be expanded, or in other words projected from the work arbor or body member I0 by a tapered head I6 formed on the upper end of a pull rod I'I projecting downwardly through the center of the work arbor. The lower end of the pull rod I'I is connected to a transverse bearing shaft IB which extends through elongated apertures I9 in the work arbor or body member Ill and projects to opposite sides thereof.

The bearing shaft I8 extends across a counterbore 20 in the lower end of the body member I0 50 and is continuously urged in a downwardly direction by a heavy compression spring ZI located in the counterbore 2D and interposed between the bottom thereof and the bearing shaft I8. The spring 2l is a very heavy spring, preferably a 55 1500 pound spring, and the bearing shaft I 8 is adapted to be raised against the force thereof to release the work by a cam member 22 rotatably supported through the medium of anti-friction bearings 23 about the lower end of the work arbor I0. The upper surface of the cam member is provided with two suitably inclined face cam tracks 25 and 26 adapted to be engaged by rollers 21 carried on opposite ends of the bearing shaft I8. Anti-friction bearings 28 interposed between the rollers and the bearing shaft I8 reduce the friction to a. minimum. The construction is such that when the cam member 22 is in such a position that the rollers are above the lowest part of the cam tracks 25 and 26, they'do not engage the same, therefore allowing the full force of the spring 20 to be exerted against the bearing shaft I8, and in turn utilized in gripping the work. It will be apparent that the cam member 22 can be readily and easily rotated in the direotion'indi'- cated by the arrow shown in Fig. 2,-to raise the bearing shaft |8'against the action of the spring 20, to release the work. The rollers 26 etc. are enclosed in a bearing shield 29 which prevents chips, etc'. from interferingwith the proper operation thereof, and which also serves as a guard for the operator.

It is believedthat the operation of the device will be apparent from the foregoing description thereof. Suffice it to say that the cam member 22 can be readily rotated or oscillated to chuck or u nchuck a work blank. In the preferred embodiment shown the periphery of the cam member 22 is provided with a plurality of holes 30 into whichv a bar or tool may be inserted to facilitate rotation of the cam, but in practice this has been found unnecessary. lWhile the preferred embodiment of the invention has been shown and described in considerable detail, it will be apparent that the invention is susceptible of various modifications and alternative constructions, and is not limited to the specic construction shown.

Having described the invention, what I claim is:

l. An Yexpandible chuck comprising a body member adapted to ,berconnected to a rotatable 'thereto and to said transverse member for continuously urging said longitudinal member in a direction to move said jaws into expanded position, a cam member rotatably supported about i the exterior of said body member and having a plurality of cam surfaces on the face thereof ladapted to engage said rollers and move said transverse or cross member against the action of saidspring, and antifriction bearings interposed between said body member and said cam member. .2. An expandible chuck comprising a lbody member havinga counterbore in one end thereof, work engaging f members carried by said body member and movable radially of the. longitudinal axis thereof, a transverse member extending through said body member and across. said counterbore and movable longitudinally thereof, a. longitudinally `extending member connected to saidtransverse member and providedwith a cam surface adapted to move said work engaging mem# ber radially, a heavy spring in said counterbore in said bodymember. and interposedA between the bottom thereof and said transverse member for continuously urging the latter ina direction to move said work engaging memers'into expanded position, rollers carried by said transverse mem-v ber-adjacent opposite endsthereof, acam member rotatably supported about saidbody'member and having a plurality of cam surfaces thereon adapted to engage saidrollers and movesaid transverse or cross member against the action of said spring, and antifriction'bearings interposedbetween said body member and said cam member.`

Y Y. O'IIS E. STAPLES. 

